The present invention relates to a current supply arrangement for an electronic remote or ripple control receiver.
The function of a remote control receiver is to selectively receive and evaluate alternating-current pulses and alternating-current pulse sequences superimposed upon a power supply system by a transmitter at a control center or central station. Accordingly, a remote control receiver generally comprises a selective receiving section which filters out pulse sequences of a certain frequency from the voltages delivered to its input. The selective receiving section is followed by a demodulator, generally in the form of a diode rectifier, which forms a d.c. voltage pulse sequence corresponding to the transmitted alternating-current pulse sequence. This direct-current pulse sequence, also known as the pulse pattern, is then evaluated in known manner by means of a time base and a comparator. The commands expressed by any one of the aforementioned alternating-current pulse sequences or by the direct-current pulse sequences obtained from them can be coded in any one of the known codes. Accordingly, the remote control receiver comprises a decoder associated with the time base. In the decoder, a received remote control command is compared with a remote control command associated with the particular receiver and, when the two remote control commands coincide with one another, a "go" signal is formed, for example in the form of a current pulse by which a switching element, for example in the form of a current pulse switch, is actuated.
Most remote control receivers comprise conventional filters, for example LC-resonant circuits or electro-mechanical resonant combinations, which are directly energized by the received, i.e. non-amplified, signal energy. The energy for the direct-current pulse sequence to be generated also emanates from the signal energy delivered to the receiver. An electro-mechanical switch mechanism operated by a synchronous motor connected to the alternating-current power supply is generally used for the time base. A relay or a controlled silicon rectifier can be used as the storage device for the comparator.
As a result of technical advances in the field of electronic semiconductor components, especially integrated circuits, it is now possible to inexpensively produce, for example, electronic filter arrangements such as, for example, active RC-filters and fully electronic circuits for comparing and evaluating pulse patterns. The only electro-mechanical switching element required is, preferably, a current pulse switch operable by the "go" signal by means of which electrical equipment connected to it can be connected to and disconnected from the power supply system in dependence upon the commands received.
In view of the relatively low d.c. voltages of, for example, 20 volts, and also in view of the fact that the electronic circuit arrangements used impose quite stringent demands upon the stability of the feed voltage delivered to them, it has hitherto been considered necessary to use a current supply arrangement incorporating a transformer and a voltage regulator for supplying current to an electronic remote control receiver.
Since, however, very large numbers of remote control receivers are often required, it is important for economic reasons to keep their manufacturing costs as low as possible. A transformer-equipped current-supply arrangement is not only expensive, but is also difficult to install in conventional printed circuits.